Trade board (4)
I believe the answer is:
Here is my best explanation:
This clue is a double definition.
'trade' is the first definition.
('deal' can be a synonym of 'trade')
'board' is the second definition.
(deal is a kind of board)
(Other definitions for deal that I've seen before include "Distribute cards or do business", "Give out (cards)", "Sawn wood", "Act of business", "Put cards on table", "act", "loss", "Distribute playing cards", "Kind of wood or bargain" and "Lead out of the pine wood".)